Abstract: The invention relates to a method for determining a physical parameter representative of a point P of a plate by means of a device comprising a first receiver for measuring a wave propagating in the plate, and a calculation unit. The method includes the following steps: measuring, by means of the first receiver, a first signal s1(t) representative of a wave propagating in the plate; defining a closed contour C on the plate surrounding said point P, the contour C being the location on the plate on which either a wave is generated by a first emitter, or the first signal s1(t) is measured; and determining the physical parameter at point P on the plate by identifying, thanks to at least said first signal, a shape function fshape(f), in the following equation: formula (I), where Wcontour and Gplate are functions of Green, and the shape function fshape(f) is dependent on the frequency f of the wave and on the physical parameter.